base

noun:the lowest part or supporting bottom of an object; a foundation on which something rests
- The ancient statue was mounted on a tall stone base.
noun:a conceptual structure or entity on which something draws or depends
- A strong knowledge of mathematics provides a solid base for studying physics.
noun:a place used as a center of operations by the armed forces or others; a headquarters
- The soldiers returned to their base after the mission.
noun:a main or important element or ingredient to which other things are added
- The sauce had a tomato base.
noun:in mathematics, the number that is raised to a power or the side of a geometric figure from which the height is measured
- In the expression 10³, the number 10 is the base.